I have recently been working on a project using Google Data Studio. It offers the ability to pretty quickly draft up a dashboard, with a wide-range of data sources. In the example that I have been working on it's really just connected to a Google sheet. It provides a pretty decent set of functionality for writing filters composed of various types of logic for rendering and creating graphs. Overall I enjoyed the end results that I got but I have some concerns with building using these types of dashboards.
One thing to note, at least at time of writing is that data studio is a bit buggy. There are some times were data fields were switching around on me for no apparent reason. I'll attribute some of these to the fact that I'm new with data studio but I am quite certain some of these fields changed out from my under my feet for no apparent reason.
Another thing that I observed happening was that the features are not fully built out yet for maximum convenience swapping filters and sharing functionality. Specifically, at the time of writing you have to remove a filter from a copied graph in order to apply a new filter. I don't think is a copy filter functionality either. I.e. Maybe you are filtering on a role of "student" vs. "employee" for some particular entry of data.
Another thing I realize is that there is a very specific framework in place for how data should be presented. I wish that there was an extensive tutorial built out that shows the idiomatic ways of presenting data to users with the options that data studio provides.
Lastly, I can't help but feel disappointed by the re-usability of all of the "code" that I generated in the particular dashboard I built out. Really I'm talking about nothing more than filters because that's where the majority of logic exists in data studio. If I were to try to re-use some of that logic, how would I go about that? It's not so clear.
Lastly, figuring out how to plot multiple bars for a single dimension in a graph was not at all easy. Ultimately I ended up using "blended" data feature for this, by selecting multiple graphs and right-clicking. But that was not easy to figure out and it was quite gimmicky. The amount of space provided in the user interface to line up your data based on a particular key, and to then choose your metrics and other configurations was very cramped. I wish that at certain points in the process of editing data, the full-screen would be utilized.
Like many things in the world of computing, it's not too bad once you get used to it. I think the strength of the tool is in how quickly you can edit and mock up a report. That said, my use case was pretty now and only data sources were a spreadsheet. For anything more complex than that, I would probably really look to make sure the data I was trying to ingest into data studio, is as streamlined and simple as possible before getting it into a database or a spreadsheet for consumption by data studio.
TL;DR It's a good tool but it's far from providing the flexibility of data manipulation that a full-fledged programming language provides. I highly recommend thinking about how to make your data simple, and a single source before using data studio.